Design And Implementation Of Decentralized Wireless Data Acquisition And Control System In A Greenhouse

As we all know, agriculture is the base of a nation. China is a large agricultural country, however, compared with Europe, the United States and other developed countries, Agricultural efficiency in China is still relatively low, and farmers in China use little technology in their farming work. Compared with traditional farming methods, greenhouse is much more efficient and more productive, and prompting agricultural greenhouses is an important means to improve the level of agriculture. Data acquisition and electromechanical equipment control are the main parts of greenhouse, in traditional wired data acquisition and control system, plenty of wires make the greenhouse very messy, and are easily aging because of the humid and acid greenhouse environment, besides, maintenance and upgrade are difficult and the cost is very expensive. As the rise and development of wireless sensor network technology, a new kind of system started to be used in greenhouse--wireless data acquisition and control system, which cost less and can be installed easily. Because of these advantages, wireless system take place of wired system quickly in some greenhouses, they are much easier to use and upgrade, and will become the mainstream in future greenhouse.Most of wireless system applied in greenhouse today are centralized system, which means that all the wireless nodes in the network will transmit their sensor data to the central node. Thus the central node becomes a super node, once breaking down, the whole system will halt. Besides, in a large greenhouse, transmission between the faraway nodes and the central node could delay for quite a long time, and transmission success rate is lower. In order to solve the problems of wireless system, a decentralized wireless data acquisition and control system is developed in this thesis. In a decentralized wireless network, there’s no central or super node, and all the nodes have the same capability, therefore a few nodes’ breaking down won’t cause much damage to the whole system, and every node only communicates with its neighbor nodes, which means that the transmission delay and transmission success rate will stay on a low level, and don’t increase even when the scale of network expands. The decentralized wireless data acquisition and control system solves the problems of centralized wireless system successfully, it provides a new wireless solution for large greenhouses, and will play an important role in future agriculture.